1. Field
The technology described herein relates to materials sortation, and related apparatus and methods.
2. Related Art
Various manufacturing and scrap processes produce small pieces of metal. For instance, as superalloy for instance as nickel or cobalt based superalloy components are processed, a tremendous amount of machine turnings are generated, such as those shown in FIG. 1. After they have been shredded, processed to remove lubricants, and dried, they are known as clean superalloy machining chips, as shown in FIG. 2.
The large number of superalloy products manufactured by the industry requires the production of a vast range of metal alloys having various compositions. The resulting wide range of alloys and scrap materials from different end user applications are returned to scrap processors for recycling and reuse. A scrap has its greatest value when it is returned to the same alloy as when originally produced, in a clean and dry condition. If a mixture of alloys can be sorted or graded into its original alloy composition, its value will increase. Absent removal of contamination via a cost effective mechanism, the value of this scrap can be worth far less than its potential value.
The value added depends upon the value of the mixed scrap and the competitive costs for producing high-grade specification alloys from scrap versus from primary virgin sources. Today, the most common automated methods for sorting scrap into grades or types at a scrap yard are: shredding or shearing, magnetic separation, eddy current separation, and heavy media separation. Some equipment purports to automatically sort metal alloys using color sensors. In most instances for sorting of typical nonferrous metal scrap, human visual recognition is the primary means for sorting one grade of scrap from another.
Handheld and bench top x-ray fluorescence (XRF) sorters are available for assisting operators in sorting superalloys. Even though this method takes several seconds per item, with superalloy scrap being so valuable, even in the U.S., this method of scrap sorting can be cost effective on large items of scrap. However, the current handheld and bench top XRF sorting technologies in existence today are not cost effective on small items of scrap such as those shown in FIG. 2. They are, therefore, also hopelessly incapable of cost effectively sorting individual machining chips of the type shown in FIG. 3, since such machining chips are even smaller than the items of FIG. 2.
Commercially efficient sortation of small pieces of metal has yet to be developed.